const showDecorator:MethodDecorator = (target:Object, propertyKey:string | symbol,descriptor:PropertyDescriptor) => {
    descriptor.writable = false;
}

class User{
    @showDecorator
    public static show(){
        console.log('houdunren.com');
    }
}

User.show = () => {
    console.log('后盾人');
};  

User.show();